<template>
  <form-item-wrapper :designer="designer" :field="field" :rules="rules" :design-state="designState"
                     :parent-widget="parentWidget" :parent-list="parentList" :index-of-parent-list="indexOfParentList"
                     :sub-form-row-index="subFormRowIndex" :sub-form-col-index="subFormColIndex"
                     :sub-form-row-id="subFormRowId">
    <!-- el-upload增加:name="field.options.name"后，会导致又拍云上传失败！故删除之！！ -->
    <el-upload ref="fieldEditor" :disabled="field.options.disabled"
               :style="styleVariables" class="dynamicPseudoAfter"
               :action="field.options.uploadURL" :headers="uploadHeaders" :data="uploadData"
               :with-credentials="field.options.withCredentials"
               :multiple="field.options.multipleSelect" :file-list="fileList"
               :show-file-list="field.options.showFileList" :class="{'hideUploadDiv': uploadBtnHidden}"
               :limit="field.options.limit" :on-exceed="handleFileExceed" :before-upload="beforeFileUpload"
               :on-success="handleFileUpload" :on-error="handelUploadError" :on-remove="handleFileRemove">
      <div slot="tip" class="el-upload__tip"
           v-if="!!field.options.uploadTip">{{ field.options.uploadTip }}
      </div>
      <i slot="default" class="el-icon-plus avatar-uploader-icon"></i>
      <template #file="{ file }">
        <div class="upload-file-list">
          <span class="upload-file-name" :title="file.name">{{ file.name }}</span>
          <a :href="file.url" download="">
            <i class="el-icon-download file-action" :title="i18nt('render.hint.downloadFile')"></i></a>
          <i class="el-icon-delete file-action" :title="i18nt('render.hint.removeFile')" v-if="!field.options.disabled"
             @click="removeUploadFile(file.name)"></i>
        </div>
      </template>
    </el-upload>
  </form-item-wrapper>
</template>

<script>
import FormItemWrapper from './form-item-wrapper'
import emitter from '@/views/lowcode/utils/emitter'
import i18n, { translate } from '@/views/lowcode/utils/i18n'
import { deepClone } from '@/views/lowcode/utils/util'
import fieldMixin from '@/views/lowcode/components/form-designer/form-widget/field-widget/fieldMixin'

let selectFileText = '\'' + translate('render.hint.selectFile') + '\''

export default {
  name: 'file-upload-widget',
  componentName: 'FieldWidget', // 必须固定为FieldWidget，用于接收父级组件的broadcast事件
  mixins: [emitter, fieldMixin, i18n],
  props: {
    field: Object,
    parentWidget: Object,
    parentList: Array,
    indexOfParentList: Number,
    designer: Object,

    designState: {
      type: Boolean,
      default: false
    },

    subFormRowIndex: { /* 子表单组件行索引，从0开始计数 */
      type: Number,
      default: -1
    },
    subFormColIndex: { /* 子表单组件列索引，从0开始计数 */
      type: Number,
      default: -1
    },
    subFormRowId: { /* 子表单组件行Id，唯一id且不可变 */
      type: String,
      default: ''
    }

  },
  components: {
    FormItemWrapper
  },
  inject: ['refList', 'formConfig', 'globalOptionData', 'globalModel'],
  data () {
    return {
      oldFieldValue: null, // field组件change之前的值
      fieldModel: null,
      rules: [],

      uploadHeaders: {},
      uploadData: {
        key: '' // 七牛云上传文件名
        // token: '',  //七牛云上传token

        // policy: '',  //又拍云上传policy
        // authorization: '',  //又拍云上传签名
      },
      fileList: [], // 上传文件列表
      uploadBtnHidden: false,

      styleVariables: {
        '--select-file-action': selectFileText
      }
    }
  },
  computed: {},
  beforeCreate () {
    /* 这里不能访问方法和属性！！ */
  },

  created () {
    /* 注意：子组件mounted在父组件created之后、父组件mounted之前触发，故子组件mounted需要用到的prop
         需要在父组件created中初始化！！ */
    this.initFieldModel()
    this.registerToRefList()
    this.initEventHandler()
    this.buildFieldRules()

    this.handleOnCreated()
  },

  mounted () {
    this.handleOnMounted()
  },

  beforeDestroy () {
    this.unregisterFromRefList()
  },

  methods: {
    handleFileExceed () {
      let uploadLimit = this.field.options.limit /* 此行不能注释，下一行ES6模板字符串需要用到！！ */
      this.$message.warning('render.hint.uploadExceed')
    },

    updateUploadFieldModelAndEmitDataChange (fileList) {
      let oldValue = deepClone(this.fieldModel)
      this.fieldModel = deepClone(fileList)
      this.syncUpdateFormModel(this.fieldModel)
      this.emitFieldDataChange(this.fieldModel, oldValue)
    },

    beforeFileUpload (file) {
      let fileTypeCheckResult = false
      let extFileName = file.name.substring(file.name.lastIndexOf('.') + 1)
      if (!!this.field.options && !!this.field.options.fileTypes) {
        let uploadFileTypes = this.field.options.fileTypes
        if (uploadFileTypes.length > 0) {
          fileTypeCheckResult = uploadFileTypes.some((ft) => {
            return extFileName.toLowerCase() === ft.toLowerCase()
          })
        }
      }
      if (!fileTypeCheckResult) {
        this.$message.error(this.i18nt('render.hint.unsupportedFileType') + extFileName)
        return false
      }

      let fileSizeCheckResult = false
      let uploadFileMaxSize = 5 // 5MB
      if (!!this.field.options && !!this.field.options.fileMaxSize) {
        uploadFileMaxSize = this.field.options.fileMaxSize
      }
      fileSizeCheckResult = file.size / 1024 / 1024 <= uploadFileMaxSize
      if (!fileSizeCheckResult) {
        this.$message.error(this.i18nt('render.hint.fileSizeExceed') + uploadFileMaxSize + 'MB')
        return false
      }

      this.uploadData.key = file.name
      return this.handleOnBeforeUpload(file)
    },

    handleOnBeforeUpload (file) {
      if (this.field.options.onBeforeUpload) {
        // let bfFunc = new Function('file', this.field.options.onBeforeUpload)
        let bfFunc = function (file) {
          return this.field.options.onBeforeUpload
        }
        let result = bfFunc.call(this, file)
        if (typeof result === 'boolean') {
          return result
        } else {
          return true
        }
      }

      return true
    },

    handleFileUpload (res, file, fileList) {
      if (file.status === 'success') {
        // this.fileList.push(file)  /* 上传过程中，this.fileList是只读的，不能修改赋值!! */
        this.updateUploadFieldModelAndEmitDataChange(fileList)
        this.fileList = deepClone(fileList)
        this.uploadBtnHidden = fileList.length >= this.field.options.limit

        if (this.field.options.onUploadSuccess) {
          // let mountFunc = new Function('result', 'file', 'fileList', this.field.options.onUploadSuccess)
          let mountFunc = function (result, file, fileList) {
            return this.field.options.onUploadSuccess
          }
          mountFunc.call(this, res, file, fileList)
        }
      }
    },

    handleFileRemove (file, fileList) {
      this.fileList = deepClone(fileList) // this.fileList = fileList
      this.updateUploadFieldModelAndEmitDataChange(fileList)
      this.uploadBtnHidden = fileList.length >= this.field.options.limit

      if (this.field.options.onFileRemove) {
        // let customFn = new Function('file', 'fileList', this.field.options.onFileRemove)
        let customFn = function (file, fileList) {
          return this.field.options.onFileRemove
        }
        customFn.call(this, file, fileList)
      }
    },

    removeUploadFile (fileName) {
      let foundIdx = -1
      let foundFile = null
      this.fileList.forEach((file, idx) => {
        if (file.name === fileName) {
          foundIdx = idx
          foundFile = file
        }
      })

      if (foundIdx >= 0) {
        this.fileList.splice(foundIdx, 1)
        this.updateUploadFieldModelAndEmitDataChange(this.fileList)
        this.uploadBtnHidden = this.fileList.length >= this.field.options.limit

        if (this.field.options.onFileRemove) {
          // let customFn = new Function('file', 'fileList', this.field.options.onFileRemove)
          let customFn = function (file, fileList) {
            return this.field.options.onFileRemove
          }
          customFn.call(this, foundFile, this.fileList)
        }
      }
    },

    handelUploadError (err, file, fileList) {
      if (this.field.options.onUploadError) {
        // let customFn = new Function('error', 'file', 'fileList', this.field.options.onUploadError)
        let customFn = function (error, file, fileList) {
          return this.field.options.onUploadError
        }
        customFn.call(this, err, file, fileList)
      } else {
        this.$message({
          message: this.i18nt('render.hint.uploadError') + err,
          duration: 3000,
          type: 'error'
        })
      }
    }

  }
}
</script>

<style lang="scss" scoped>
@import "../../../../../../styles/global"; //* form-item-wrapper已引入，还需要重复引入吗？ *//

.full-width-input {
  width: 100% !important;
}

.dynamicPseudoAfter ::v-deep .el-upload.el-upload--text {
  color: $--color-primary;
  font-size: 12px;

  .el-icon-plus:after {
    content: var(--select-file-action);
  }
}

.hideUploadDiv {
  ::v-deep div.el-upload--picture-card { /* 隐藏最后的图片上传按钮 */
    display: none;
  }

  ::v-deep div.el-upload--text { /* 隐藏最后的文件上传按钮 */
    display: none;
  }

  ::v-deep div.el-upload__tip { /* 隐藏最后的文件上传按钮 */
    display: none;
  }
}

.upload-file-list {
  font-size: 12px;

  .file-action {
    color: $--color-primary;
    margin-left: 5px;
    margin-right: 5px;
    cursor: pointer;
  }
}

</style>
